package cn.walnut.secutiry.core.validate.code;

import cn.walnut.secutiry.core.properties.SecurityProperties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.social.connect.web.HttpSessionSessionStrategy;
import org.springframework.social.connect.web.SessionStrategy;
import org.springframework.web.bind.ServletRequestUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.ServletWebRequest;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

/**
 * @program: walnut-security
 * @Date: 2018/12/23 0:09
 * @Author: Walnut1992
 * @Description:
 */
@RestController
public class ValidateCodeController {

    public static final String SESSION_KEY = "SESSION_KEY_IMAGE_CODE";

    private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();

    @Autowired
    private SecurityProperties securityProperties;

    @GetMapping("/code/image")
    public void createCode(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws IOException {
        ImageCode imageCode = createImageCode(new ServletWebRequest(httpServletRequest));
        // 将验证码放到session中
        sessionStrategy.setAttribute(new ServletWebRequest(httpServletRequest), SESSION_KEY, imageCode);
        ImageIO.write(imageCode.getImage(), "JPEG", httpServletResponse.getOutputStream());
    }

    private ImageCode createImageCode(ServletWebRequest servletWebRequest) {

        int width = ServletRequestUtils.getIntParameter(servletWebRequest.getRequest(),"width", securityProperties.getCode().getImage().getWidth());
        int height = ServletRequestUtils.getIntParameter(servletWebRequest.getRequest(), "height", securityProperties.getCode().getImage().getHeight());
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        Graphics graphics = image.getGraphics();
        Random random = new Random();

        graphics.setColor(getRandColor(200, 250));
        graphics.fillRect(0, 0, width, height);
        graphics.setFont(new Font("Times New Roman", Font.ITALIC, 20));
        graphics.setColor(getRandColor(160, 200));
        for (int i = 0; i < 155; i++) {
            int x = random.nextInt(width);
            int y = random.nextInt(height);
            int xl = random.nextInt(12);
            int yl = random.nextInt(12);
            graphics.drawLine(x, y, x + xl, y + yl);
        }
        String sRand = "";
        for (int i = 0; i < ServletRequestUtils.getIntParameter(servletWebRequest.getRequest(), "length", securityProperties.getCode().getImage().getLength()); i++) {
            String rand = String.valueOf(random.nextInt(10));
            sRand += rand;
            graphics.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
            graphics.drawString(rand, 13 * i + 6, 16);
        }
        graphics.dispose();

        return new ImageCode(image, sRand, ServletRequestUtils.getIntParameter(servletWebRequest.getRequest(), "expireIn", securityProperties.getCode().getImage().getExpireIn()));
    }

    /**
     * 生成随机背景条纹
     *
     * @param fc
     * @param bc
     * @return
     */
    private Color getRandColor(int fc, int bc) {
        Random random = new Random();
        if (fc > 255) {
            fc = 255;
        }
        if (bc > 255) {
            bc = 255;
        }
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }
}
